Here’s the thing: concentrating on other peoples’ foibles can lead to nothing but frustration. It’s like a person trying to get their spouse to “change”. The only direct control we have is over ourselves (and then even if that, since all of us are to some degree or another addicted to our passions!).
Concerning the Mass, there will always be people who don’t know, don’t want to make the effort to know, don’t care, mumble and not sing/respond, don’t say anything, don’t make the right gestures, and the list goes on. It’s got nothing to do with the form of the Mass either; many older folks used to pre-Vatican II can tell you about the men outside smoking during Mass, not responding because it wasn’t a dialogue Mass, leaving after communion, etc.
If one does care about those things, then one does them one’s self and works out one’s own salvation with “trembling and fear”, and leave the rest up to God’s Grace and mercy; Lord knows even those of us who know and do the correct gestures and responses at Mass, still need plenty of that Grace and Mercy. There’s no way of knowing that the person who is lackadaisical about Mass gestures isn’t really already a saint known to God, caring for the elderly, donating his or her time to a homeless shelter, soup kitchen or hospital, etc.
We’re human, and humanity is often messy, and what count’s is what’s inside…